Buggy code:
public class JavaProject extends Openable implements IProjectNature , IJavaProject { protected static final String [ ] NO_PREREQUISITES = new String [ 0 ] ; protected static final boolean IS_CASE_SENSITIVE = ! ( new File ( "Temp" ) . equals ( new File ( "temp" ) ) ) ; protected IProject fProject ; public JavaProject ( ) { } public JavaProject ( IProject project , IJavaElement parent ) { } protected void addToBuildSpec ( String builderID ) throws CoreException { } public static IPath canonicalizedPath ( IPath externalPath ) { } protected void closing ( Object info ) throws JavaModelException { } public IPackageFragmentRoot [ ] computePackageFragmentRoots ( boolean retrieveExportedRoots ) { } public void computePackageFragmentRoots ( ObjectVector accumulatedRoots , HashSet rootIDs , boolean insideOriginalProject , boolean checkExistency , boolean retrieveExportedRoots ) { } public void computePackageFragmentRoots ( IClasspathEntry entry , ObjectVector accumulatedRoots , HashSet rootIDs , boolean insideOriginalProject , boolean checkExistency , boolean retrieveExportedRoots ) { } public String computeSharedPropertyFileName ( QualifiedName qName ) { } public void configure ( ) throws CoreException { } protected OpenableElementInfo createElementInfo ( ) { } public void deconfigure ( ) throws CoreException { } protected IClasspathEntry [ ] defaultClasspath ( ) throws JavaModelException { } protected IPath defaultOutputLocation ( ) throws JavaModelException { } public boolean equals ( Object o ) { } public IJavaElement findElement ( IPath path ) throws JavaModelException { } public IPackageFragment findPackageFragment ( IPath path ) throws JavaModelException { } public IPackageFragmentRoot findPackageFragmentRoot ( IPath path ) throws JavaModelException { } protected boolean generateInfos ( OpenableElementInfo info , IProgressMonitor pm , Map newElements , IResource underlyingResource ) throws JavaModelException { } public IPackageFragmentRoot [ ] getAllPackageFragmentRoots ( ) throws JavaModelException { } public IPackageFragmentRoot [ ] getBuilderRoots ( IResourceDelta delta ) throws JavaModelException { } public void computeBuilderRoots ( IResourceDelta delta , ArrayList builderRoots , HashSet rootIDs , boolean insideInitialProject ) throws JavaModelException { } protected String getClasspathAsXMLString ( IClasspathEntry [ ] classpath , IPath outputLocation ) throws JavaModelException { } public IClasspathEntry getClasspathEntryFor ( IPath path ) throws JavaModelException { } public QualifiedName getClasspathPropertyName ( ) { } protected static Element getEntryAsXMLElement ( Document document , IClasspathEntry entry , IPath prefixPath ) throws JavaModelException { } protected char getHandleMementoDelimiter ( ) { } private ICommand getJavaCommand ( IProjectDescription description ) throws CoreException { } public IJavaProject getJavaProject ( ) { } protected JavaProjectElementInfo getJavaProjectElementInfo ( ) throws JavaModelException { } public NameLookup getNameLookup ( ) throws JavaModelException { } public Object [ ] getNonJavaResources ( ) throws JavaModelException { } public IPath getOutputLocation ( ) throws JavaModelException { } public IPackageFragmentRoot getPackageFragmentRoot ( String jarPath ) { } public IPackageFragmentRoot getPackageFragmentRoot ( IResource resource ) { } public IPackageFragmentRoot getPackageFragmentRoot ( IPath path ) { } public IPackageFragmentRoot [ ] getPackageFragmentRoots ( ) throws JavaModelException { } protected IPackageFragmentRoot [ ] getPackageFragmentRoots ( IPath path ) throws JavaModelException { } public IPackageFragmentRoot [ ] getPackageFragmentRoots ( IClasspathEntry entry ) { } public IPackageFragment [ ] getPackageFragments ( ) throws JavaModelException { } public IPackageFragment [ ] getPackageFragmentsInRoots ( IPackageFragmentRoot [ ] roots ) { } public IProject getProject ( ) { } public IClasspathEntry [ ] getRawClasspath ( ) throws JavaModelException { } public String [ ] getRequiredProjectNames ( ) throws JavaModelException { <START_BUG> return this . projectPrerequisites ( getExpandedClasspath ( true ) ) ; <END_BUG> } public IClasspathEntry [ ] getResolvedClasspath ( boolean ignoreUnresolvedVariable ) throws JavaModelException { } public IClasspathEntry [ ] getResolvedClasspath ( boolean ignoreUnresolvedVariable , boolean generateMarkerOnError ) throws JavaModelException { } public IClasspathEntry [ ] getExpandedClasspath ( boolean ignoreUnresolvedVariable ) throws JavaModelException { } public IClasspathEntry [ ] getExpandedClasspath ( boolean ignoreUnresolvedVariable , boolean generateMarkerOnError ) throws JavaModelException { } private void computeExpandedClasspath ( JavaProject initialProject , boolean ignoreUnresolvedVariable , boolean generateMarkerOnError , HashSet visitedProjects , ObjectVector accumulatedEntries ) throws JavaModelException { } public ISearchableNameEnvironment getSearchableNameEnvironment ( ) throws JavaModelException { } public String getSharedProperty ( QualifiedName key ) throws CoreException { } public SourceMapper getSourceMapper ( ) { } public IResource getUnderlyingResource ( ) throws JavaModelException { } public boolean hasBuildState ( ) { } public boolean hasClasspathCycle ( IClasspathEntry [ ] entries ) { } public int hashCode ( ) { } public boolean hasSource ( ) { } public boolean isClasspathEqualsTo ( IClasspathEntry [ ] otherClasspathWithOutput ) throws JavaModelException { } static int kindFromString ( String kindStr ) { } static String kindToString ( int kind ) { } public String loadClasspath ( ) throws JavaModelException { } public IEvaluationContext newEvaluationContext ( ) { } public ITypeHierarchy newTypeHierarchy ( IRegion region , IProgressMonitor monitor ) throws JavaModelException { } public ITypeHierarchy newTypeHierarchy ( IType type , IRegion region , IProgressMonitor monitor ) throws JavaModelException { } protected void openWhenClosed ( IProgressMonitor pm , IBuffer buffer ) throws JavaModelException { } private String [ ] projectPrerequisites ( IClasspathEntry [ ] entries ) throws JavaModelException { } protected IClasspathEntry [ ] readPaths ( String xmlClasspath ) throws IOException { } protected void removeFromBuildSpec ( String builderID ) throws CoreException { } public void updatePackageFragmentRoots ( ) { } private IResource retrieveResource ( IPath path , IResourceDelta delta ) throws JavaModelException { } public IJavaElement rootedAt ( IJavaProject project ) { } public String rootID ( ) { } public boolean saveClasspath ( boolean force ) throws JavaModelException { } private void setJavaCommand ( IProjectDescription description , ICommand newCommand ) throws CoreException { } public void setOutputLocation ( IPath outputLocation , IProgressMonitor monitor ) throws JavaModelException { } public void setProject ( IProject project ) { } public void setRawClasspath ( IClasspathEntry [ ] entries , IProgressMonitor monitor ) throws JavaModelException { } public void setRawClasspath ( IClasspathEntry [ ] entries , IPath outputLocation , IProgressMonitor monitor ) throws JavaModelException { } public void setRawClasspath ( IClasspathEntry [ ] newEntries , IPath newOutputLocation , IProgressMonitor monitor , boolean canChangeResource , boolean forceSave , IClasspathEntry [ ] oldClasspath ) throws JavaModelException { }

Fix:
return this . projectPrerequisites ( getResolvedClasspath ( true ) ) ;